TABLE CONTENTS

Quantitative Detection of the Major Plant-parasitic Nematodes in Japan
using Real-time PCR
Toyota, K., E. Sato, T. Shirakashi & Y.Y. Min
Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and
Technology, Koganei, Tokyo 184-8588, Japan
Four primer sets in real-time PCR were designed for the quantitative detection of the rootlesion
nematode (Pratylenchus penetrans), the root-knot nematode (Meloidogyne incognita),
the potato cyst nematode (Globodera rostochiensis) and the soybean cyst nematode
(Heterodera glycine). These primer sets were highly specific to the corresponding species
according to the previous sequences in database, except for the one for M. incognita, which
will detect M. arenaria and M. javanica. Different numbers of the second-stage juveniles
(J2) of P. penetrans were mixed with various stages of free-living nematodes and then DNA
was extracted from the nematode mixture. There was a significant correlation between the Ct
values and the number of P. pentrans added. Highly significant correlations were also
observed in M. incognita, G. rostochiensis and H. glycine. Real-time PCR sensitively
detected only a single plant-parasitic nematode in 200 to 1000 individuals of free-living
nematodes. This study demonstrated that real-time PCR assay for the major plant-parasitic
nematodes provides a sensitive and reliable means for the rapid quantification of the
vermiform pests
Application of Taylor's Power Law to Sample Statistics of Nematodes
Associated with Cucurbits in Egypt
Abd-Elgawad , M.M. (1), A.E. Wahab (2), F.H. Koura (1), M.M.A. Hammam & S. Haroon
(1) Phytopathology Department, National Research Center, El-Tahrir St., Dokki 12622, Giza, Egypt; (2)
Department of Agriculural Zoology and Nematology, Faculty of Agriculture, Al-Azhar University.
Taylor's power law could be fitted (P ≤ 0.01) to most of the common nematode genera
extracted from the rhizosphere of cucurbitaceous crops in Egypt. These nematode genera
were arranged in an ascending order according to their index of dispersion (represented by
slope values of the power law) in soil as follows: Tylenchus, Pratylenchus,
Tylenchorhynchus, Heterodera, Meloidogyne and Hirschmanniella. The spatial distribution
of most nematode genera was aggregated which can confound parametric statistical analyses
necessary to study their effects on the different cucurbitaceous hosts. Yet, approaches based
on estimate of such dispersion indices may be used to solve these problems and in the development
and evaluation of control measures. Also, the law was used for sample size
optimization. For example, to sample Tylenchus spp. and Meloidogyne spp. from one feddan
(4200 m2) cucurbitaceous area with a 0.25 standard error to mean ratio and 5 nematodes/100
gm soil, one could collect one and twenty samples, respectively.
5 th International Congress of Nematology, 2008 325